基于双谱二次特征的通信信号识别算法研究*

针对卫星通信中辐射源信号分类识别问题，开展基于双谱二次特征的卫星通信信号分类识别算法研究。通过辐射源信号的对角切片双谱获取信号特征，利用Chirp-Z变换将双谱对角切片特征从频域扩展至复平面，并提出扩展的基于巴式（Bhattacharyya）距离的分离度准则作为信号双谱二次特征提取依据，提取出具有最强可分离度特征作为特征参数，并通过支持向量机进行分类识别仿真实验。实验表明，本文识别算法适用于不同类型的卫星通信信号，且对噪声变化不敏感，可实现较高的正确识别率。

Research of Signal Identification AlgorithmBased on Bispectrum Cascade Feature

To deal with the problem of signal identification in satellite communication, this paper developed a new identification algorithm based on bispectrum cascade feature. It could obtain signal feature by analyzing the diagonal slice of the spectrum. By using Chirp-Z transform, the algorithm enlarged the diagonal slice of the spectrum from the frequency domain to the Z-plane. It could extract bispectrum cascade feature according to the extended Bhattacharyya distance measurement and obtain the most powerful detachable features as the feature parameters. By Support Vector Machine (SVM), this paper simulated the processing of signal identification. The results show that the method is suitable for different types of communication signals. The algorithm is not sensitive to noise and can achieve identification accuracy above 90% .